Origin: picture the female perineum in the missionary position, and note the orientation of the vulva relative to the anus. Observce the similarities with the typical orientation of the front door and the cat flap in a house.
Other parallels regarding size and ease of human access further strengthen this metaphor.
"I've got the painters in this week, but you can go in through the cat flap if you like"
When someone waves their hands (the "flags") by rotating about their wrists while talking, which makes them seem gay.
Coined by Mark of FuzzySneaker.com on December 17, 2006.
Peter: (while waving his hands about his wrists a bit too much) So I was concerned about how well I was doing in the class, so I went up to the professor afterwards...
Mark: Yo...Pete...put away the fag flags.